Pintle hook



Dec. 3, 1963 A. NOVQTNEY 3,112,833

PINTLE HOOK Filed April 25} 1962 INVENTOR.

FRANK A. Move-may by M, Aw WAT-r0 2M E76 United States Patent 3,112,833 PINTLE HOOK Frank A. Novotney, Tonica, 111., assignor to Anthony (Iompany, a corporation of Illinois Filed Apr. 25, 1962, Ser. No. 190,1fl0 QCIaims. (61214-77) Hydraulically operated lift gate platforms, for lifting a load from ground level to the level of the floor or body of a truck are commonly applied to truck frames and travel with the truck from place to place and form an integral part of the truck. With such lift gate platforms, the platform itself is supported and elevated by a parallelogram linkage mechanism actuated by a hydraulic cylinder and piston. The lift gate platform and linkage mechanism for elevating and lowering the lift gate, extending across the back of the truck body, and the hydraulic cylinder and piston for actuating the linkage mechanism are located in the center of the back of the truck body or chassis so that it is not possible to mount a hook on the truck when it is desired to tow another vehicle or to connect the truck to another vehicle to be towed by the other vehicle.

It has been attempted to remedy this deficiency by attaching a pintle hook to the parallel arms which raise and lower the lift gate platform. Due, however, to the severe loading conditions to which lift gate mechanism is subjected under such an arrangement, the lift gate mechanism is frequently damaged, with the result that such an arrangement for attaching the pintle hook to the truck body is impractical and undesirable, and is not conducive to long life and efficient operation of the lift gate mechanism.

A principal object of the present invention, therefore, is to remedy the foregoing deficiencies by providing a pintle hook mechanism attached to the lift gate mechanism, and so arranged that the towing loads are taken on the truck frame rather than the lift gate mechanism.

A further object of the invention is to provide a simplified and efiicient towing attachment mounted on the mechanism for elevating the lift gate platform and elevated with the elevating mechanism for the platform into registry with the truck frame whereby the loads of towing are taken on the truck frame rather than the lift gate mechanism.

A still further object of the invention is to provide a pintle hook mechanism for lift gate platforms attached to the rear of truck frames in which the pintle hook mechanism is elevated by the elevating arms for the lift gate mechanism, into position to register with the truck frame, whereby the loads on the pintle hook are transmitted to the truck frame and relieved from the lift gate mechanism.

These and other objects of the invention will appear from time to time as the following specification proceeds and with reference to the accompanying drawing where- FIGURE 1 is a fragmentary rear end view of a truck frame, showing a lift gate mechanism constructed in accordance with the principles of the present invention attached thereto, with the lift gate mechanism in an upright closed position;

FIGURE 2 is a fragmentary sectional View taken substantially along line II-II of FIGURE 1 and drawn to a reduced scale;

FIGURE 3 is a partial enlarged rear end view of the pintle hook mechanism shown in FIGURE 1; and

FIGURE 4 is a partial fragmentary plan view of the pintle hook mechanism, showing the plate to which a towing pin may be attached.

In the embodiment of the invention illustrated in the drawings, FIGURE 1 generally shows a lift gate platform 10 in an elevated or closed upright position, extending vertically of a truck frame 11. The lift gate platform 10 is raised and lowered and supported in elevated and lowered positions by a pair of laterally spaced outer arm members 12 extending along the outside of the truck frame and inner arm members 13 extending along the inside of the truck frame.

A hydraulic cylinder and piston 15 is pivotally connected at its head end to a support frame structure 16 for the arm members 12 and 13 and is pivotally connected at its piston rod end to a cross head 17, trunnioned between two spaced arms 18, spaced inwardly of the arms 13 and extending parallel thereto.

The arms 18 are mounted at their inner ends on a cross member 19 connected between the arm members 13, adjacent the inner ends thereof, and are connected at their outer ends to a cross member 20 connected between the arm members 13, adjacent the outer ends thereof.

The arm members 12 and 13 are transversely pivoted at their inner or lower ends to brackets 22 and 22a respectively extending from the support frame structure 16, and form in effect a parallelogram linkage arrangement for raising and lowering the lift gate platform 10 in a plurality of parallel planes. The outer arm members 12 are pivotally connected to the lift gate platform by pivot pins 21 extending through spaced bracket members 23. The inner arm members 13 are pivotally connected to the lift gate platform in spaced relation with respect to the outer arm members 12 on pivot pins 24, extending through parallel spaced bracket members 25, extending from the bottom or rear end portion of the lift gate platform, in a manner similar to that shown and described in Patent No. 2,480,528 which issued to L. W. Wachter on August 30, 1949 and no part of the present invention so not herein shown or described further.

The frame structure 15 for supporting the lift gate mechanism is suitably suspended from channels 27 forming the side frame members of the truck frame 11 and extending longitudinally along the truck frame and supporting sills 28, supporting the floor of the truck body.

Referring now in particular to the pintle hook or towing device connection of the present invention, a tubular cross member 29 is shown in FIGURE 1 as extending across the inner arms 13 and as being spaced outwardly along said arms from the cross member 19 into position to register with the channels 27 of the truck frame 11. The tubular cross member 29 is located inwardly of the pivot pins 24 along the arms 13 a distance determined by the stack or floor height of the truck body when the lift gate platform is in a horizontal loading position and level with the floor of the body of the truck. This will posit-ion the cross member 29 above the bottom flanges of the channels 27 and preferably intermediate or half way between the flanges of said channels when the lift gate platform is in the closed position shown in FIGURE 1.

As shown in FIGURES 2 and 4, the cross member 29* is welded or other-wise secured to brackets or supports 30 extending radially of the arm members 13 and welded or otherwise secured to said arm members. The tubular cross member 29 is shown as having locking pins 31 slidably mounted in opposite ends thereof and biased in out wardly extending relation with respect to said cross member by a compression spring 33. The compression spring 33 is mounted in the cross member 29 and engages the inner ends of the locking pins 31 at its opposite ends. Each locking pin 31 has a pin or machine screw 35 threaded therein and extending radially therefrom through a bayonet like slot 36. The bayonet like slot 36 has a rectilinear portion 37 extending longitudinally along the cross member 29, which terminates into a laterally spaced rounded locking notch 39 into which the pin 35 may be moved when the associated locking pin 31 is retracted within the cross member 29 and it is desired to lock said locking pin in a retracted position.

A pintle hook plate 41 is welded or otherwise secured to the cross member 29 intermediate its ends and extends radially of said cross member in a generally horizontal direction when the lift gate platform and lift gate mechanism are in the elevated closed position shown in FIG- URE 1. The pintle hook plate has an apertured portion 43 through which a towing hook may extend.

The locking pins 31 are adapted to register with the hollow interior portions of hollow bosses 44 mounted on and extending from support plates 45 extending within the flanges of the channels 27 and welded or otherwise secured thereto.

It should here be understood that the hollow bosses 44 may extend inwardly or outwardly of the plate 45 and that the plate 45 is drilled in registry with the hollow interior portion of said hollow bosses. Whether the hollow bosses extend outwardly of the channels 27 or inwardly of the flanges of said channels toward the webs thereof, depends upon the spacing of the opposite ends of the cross member 29 from the channels 27. It being desirable to space opposite ends of the cross member 29 relatively close to the inner ends of the hollow bosses 44 and the holes drilled through the plates 45, depending upon the positions of said plate and said hollow bosses with respect to the channels 27 to .which they are secured.

It may be seen from the foregoing that as the lift gate platform 10 is moved to its elevated or closed positions shown in FIGURE 1, that opposite ends of the cross member 29 will register with the hollow bosses 44, to accommodate the locking pins 31 to move within the hollow interior portions of said bosses upon release of the pins or machine screws 35 from the locking notches 39 of the bayonet slots 36. With the locking pins so engaged, all towing loads taken on the cross member 29 are relieved from the arm members 13 and taken directly on the channels 27 of the truck frame. This not only provides a simple and effective towing means, but also avoids damage to the arms 13 and the entire lift gate mechanism when a towing hook is attached to the apertured portion of the pintle hook plate 41 and the truck is either towing another truck or is being towed.

While I have herein shown and described one form in which my invention may be embodied, it may readily be understood that various variations and modifications in the invention may be attained without departing from the spirit and scope of the novel concepts thereof as defined by the claims appended hereto.

I claim as my invention:

1. -In a lift gate platform and in combination with a vehicle having parallel spaced longitudinally extending side frame members,

an elevating mechanism for said lift gate platform for raising and lowering said lift gate platform in a plurality of parallel planes,

and towing hook attaching means mounted on said elevating mechanism for interengagement with said side frame members,

and accommodating a towing hook to be attached to the vehicle and transferring the loads of towing from said elevating mechanism directly onto said side frame members comprising a member carried by said elevating mechanism in position to register with said side frame members,

and a hook attachment carried by said member and locking means carried by said member and selectively operable to have interengagement with said side frame members.

2. In a lift gate platform and in combination with a vehicle having parallel spaced longitudinally extending side frame members,

pairs of inner and outer arms transversely pivoted to the vehicle frame for movement about vertically spaced parallel axes,

a lift gate platform,

pivotal supporting connections between the outer ends of said arms and said lift gate platform,

means for actuating said arms to raise and lower said lift gate platform in a plurality of parallel planes,

and towing hook attaching means carried by two of said arms and selectively operable to have interengagement with said side frame members,

to accommodate the attachment of a tow rope to the vehicle and taking the loads of towing directly on the vehicle frame comprising a member carried by said elevating mechanism in position to register with said side frame members when said lift gate platform is in an elevated position,

a hook attachment carried by said member and locking means carried by said member and selectively operable to have interengagement with said side frame members.

3. In a lift gate platform and in combination with a vehicle having parallel spaced longitudinally extending side frame members,

pairs of inner and outer arms transversely pivoted to the vehicle frame for movement about vertically spaced parallel axes,

a lift gate platform,

pivotal supporting connections between the outer ends of said arms and said lift gate platform,

means for actuating said arms to raise and lower said lift gate platform in a plurality of parallel planes,

and towing hook attaching means carried by two of said arms and selectively operable to have interengagement with said side frame members,

to accommodate the attachment of a tow rope to the vehicle and taking the loads of towing directly on the vehicle frame,

comprising a cross member carried by the inner of said arms in position to register with said side frame members when said lift gate platform is in an elevated position,

a hook attachment carried by said cross member,

and means slidably carried by said cross member and selectively operable to have interengagement with said side frame members,

to transfer the loads of towing from said cross member directly to said side frame members.

4. In a lift gate platform and in combination with a vehicle having parallel spaced longitudinally extending side frame members,

pairs of inner and outer arms transversely pivoted to the vehicle frame for movement about vertically spaced parallel axes,

a lift gate platform,

pivotal supporting connections between the outer ends of said arms and said lift gate platform,

means for actuating said arms to raise and lower said lift gate platform in a plurality of parallel planes,

and towing hook attaching means carried by two of said arms and selectively operable to have interengagement with said side frame members,

to accommodate the attachment of a tow rope to the vehicle and taking the loads of towing directly on the vehicle frame,

comprising a cross member carried by the inner of said arms and projecting laterally beyond opposite sides thereof into positions adjacent said side frame members,

abutment means on said side frame members,

and means slidably carried by said cross member and biased to project beyond opposite ends thereof for engagement with said abutment means,

to transfer the loads of towing directly to said side frame members.

5. In a lift gate platform and in combination with a vehicle having a vehicle frame having parallel spaced longitudinally extending side frame members,

pairs of inner and outer arms pivotally connected to the vehicle frame for movement about vertically spaced transverse axes,

a lift gate platform,

pivotal supporting connections between said arms and said lift gate platform,

hydraulic cylinder and piston means operatively connected with the inner of said arms for moving said arms vertically and elevating and lowering said platform in a plurality of parallel planes,

a cross member carried by the inner of said arms and projecting laterally of said arms into position adjacent said side frame members,

a hook attachment carried by said cross frame member,

locking pins slidably carried by said cross member,

means biasing said locking pins to project from opposite ends of said cross member, other means manually operable to retractibly move said locking pins and retain said locking pins in retracted relation with respect to said cross member,

and abutment members mounted on said side members and adapted to be engaged by said locking pins when projected from opposite ends of said cross member and to take the loads of towing.

6. In a lift gate plat-form and in combination with a vehicle having a vehicle frame having parallel spaced longitudinally extending side frame members,

pairs of inner and outer arms pivotally connected to the Vehicle frame for movement about vertically spaced transverse axes,

a lift gate platform,

pivotal supporting connections between said arms and said lift gate platform,

hydraulic cylinder and piston means operatively connected with the inner of said arms for moving said arms vertically and elevating and lowering said platform in a plurality of parallel planes,

a tubular cross member mounted on the inner of said arms intermediate the ends thereof into position to register with said side frame members when said lift gate platform is in an elevated position,

locking pins slidably carried by said tubular member,

and socket members carried by said side frame members and adapted to be engaged by said locking pins and transmit the towing loads from said arms to said frame members of the vehicle frame.

7. In a lift gate platform and in combination with a vehicle having a vehicle frame having parallel spaced longitudinally extending side frame members,

pairs of inner and outer arms pivotally connected to the vehicle frame for movement about vertically spaced transverse axes, a lift gate platform,

pivotal supporting connections between said arms and said lift gate platform,

hydraulic cylinder and piston means operatively connected with the inner of said arms for moving said arms vertically and elevating and lowering said platform in a plurality of parallel planes,

a tubular cross member mounted on the inner of said arms intermediate the ends thereof into position to register with said side frame members when said lift gate platform is in an elevated position,

locking pin-s slidably carried by said tubular member,

a compression spring biasing said locking pins to project beyond opposite ends of said tubular member, socket members carried by said side frame members and adapted to be engaged by said locking pins and transmit the towing loads from said arms to said side frame members of the vehicle frame,

manually operable release means connected to said locking pins and extending radially therefrom,

and locking means for said release means for locking said locking pins in retracted pesitions with respect to said cross member.

8. In a pintle hook attachment mounted on an elevating mechanism for lift gate platforms for trucks and the like and transferring the loads of towing from the elevatin g mechanism to the truck frame,

a hollow cross member,

attachment means intermediate the ends of said cross member,

accommodating a towing rope to be attached thereto,

locking pins slidably carried in said cross member and projectible beyond opposite ends thereof into position to have interengagement with the truck frame,

and manually operable means retractibly moving said pins and locking said pins in retracted relation with respect to the truck frame.

9. In a pintle hook attachment mounted on an elevating mechanism for lift gate platforms for trucks and the like and transferring the loads of towing from the elevating mechanism to the truck frame,

a hollow cross member,

attachment means intermediate the ends of said cross member,

accommodating a towing rope to be attached thereto,

locking pins slidably carried in said cross member,

a compression spring carried by said cross member and projecting said pins beyond opposite ends of said cross member into position to have interengagement with the truck frame,

bayonet slots in said cross member,

"and manually operable means extending from said pins through said slots, for retracti'bly moving said pins and locking said pins in retracted relation with respect to said cross member.

References Cited in the file of this patent UNITED STATES PATENTS UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,112,833 December 3, 1963 Frank A. Novotney It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 1, lines 8, l2, l5, 16, 26, 27, 28, 32, 36, 38, 41, 44, 47, 49, 52, 59, 61 and 72, column 2, lines 2, 24, 26, 29, 32, 37, 51 and 56, column 3, lines 9, 31, 43, 55, 58, 59 and 75, column 4, lines 6, 8, l0, 18, 24, 30, 32, 34, 43, 51, 57, 59 and 61, column 5, lines 3, 9, ll, 30, 36, 38, 46, 52 and 58, and column 6, lines 2, 9, 24 and 38, for "lift", each occurrence, read tail Signed and sealed this 23rd day of June 1964,

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Allesting Officer Commissioner of Patents 

1. IN A LIFT GATE PLATFORM AND IN COMBINATION WITH A VEHICLE HAVING PARALLEL SPACED LONGITUDINALLY EXTENDING SIDE FRAME MEMBERS, AN ELEVATING MECHANISM FOR SAID LIFT GATE PLATFORM FOR RAISING AND LOWERING SAID LIFT GATE PLATFORM IN A PLURALITY OF PARALLEL PLANES, AND TOWING HOOK ATTACHING MEANS MOUNTED ON SAID ELEVATING MECHANISM FOR INTERENGAGEMENT WITH SAID SIDE FRAME MEMBERS, AND ACCOMMODATING A TOWING HOOK TO BE ATTACHED TO THE VEHICLE AND TRANSFERRING THE LOADS OF TOWING FROM SAID ELEVATING MECHANISM DIRECTLY ONTO SAID SIDE FRAME MEMBERS COMPRISING A MEMBER CARRIED BY 